Hiding the image
In order to draw the audience's full attention to the
presenter, you can use 
on the projector or Blank on the remote control to hide the screen image. Press any key on the projector or remote control to restore the image. The word 'BLANK' appears at the lower right corner of the screen while the image is hidden.
You can set the blank time in the SYSTEM SETUP: Basic > Blank Timer menu to let the projector return the image automatically after a period of time when there is no action taken on the blank screen.
Once Blank is pressed, the projector enters Economic mode automatically.
CAUTION
Do not block the projection lens from projecting as this could cause the blocking object to become heated and deformed or even cause a fire.
Locking control keys
With the control keys on the projector locked, you can prevent your projector settings from being changed accidentally (by children, for example). When the Panel Key Lock is on, no
control keys on the projector will operate except II POWER.
1.Press 
on the projector or go to the
SYSTEM SETUP: Basic > Panel Key
Lock menu, and select On by pressing 
/ 
on the projector or remote control. 2. A confirmation message is displayed. Select Yes to confirm.
To release panel key lock, press and hold 
for 3 seconds on the projector.
You can also use the remote control to enter the SYSTEM SETUP: Basic > Panel Key Lock and press 
/ 
to select Off.
• Keys on the remote control are still functional when panel key lock is enabled.
•If you press II POWER to turn off the projector without disabling panel key lock, the projector will still be in locked status the next time it is turned on.